If the batteries are of the same type, i.e. both are NiMH or both are Lithium-ion, then you can use a higher capacity (i.e. higher mAh) battery instead of the lower one. The reverse is also true.
People visiting Table Rock are not allowed beyond the Mill Creek Watershed boundary, which is clearly marked with numerous signs. As mentioned earlier, the Mill Creek Watershed is a closed watershed and no public access is allowed, as it is the municipal water source for the city of Walla Walla, Washington.
Chimney Rock (properly known as Washington Valley Park) is a small network of rugged intermediate trails that earns its name as The Rock by some locals. Like its central Jersey couterpart Six Mile Run this park does not drain well so please avoid after heavy rains.